Temperature humidity & possible problems when growing under LED organically

I actually have 20 of your pineapple Kush f4s in my fridge :fist_right::fist_left:, wish i could give them a Good Life at some point… LoL

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So you think adding some t5ho in these veg tents will fix my problem?

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Here’s some readings with ppfd meter

The ohitu Bio may be at most 50 to at Best 35 ppfd off frim an apogee (tested at grow shop)

The lovely lil hoe in last pics was the worst looker yesterday, put outside at 9am yesterday, its completely turned around, like you can sit back and watch its chlorosis go away, red veins gone

My 2 kitchen counter under cabinet florescent clone’s are doing ok at least lol

Bro dont post your phone number lmao

Do that in a private message buddy

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Heres a link to the vpd and led info

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Personal phone information has been removed from your earlier posting for safety reasons. Consider using a PM if you’d like to provide private information.

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Just FYI, CMH aren’t the same as MH or HPS. They grow more similar to LEF than MH in my experience.

I am a long time MH + HPS + t5 fluorescent grower who has also switched over to LED lights in the last few (ish) years. I grew under MH/HPS for 15+ years and agree they are much easier to grow healthy plants under, at least for me.

I also tried CMH for veg. In my opinion, CMH grow more like LED than MH as far as being much less forgiving and seeing more issues with deficiencies and stuff. I saw some of those same leaf issues you’re seeing under CMH.

I had (and sometimes still have) similar issues to you vegging with LED. I ended up buying some used t5 flouros last year to veg under and it was night and day. Super healthy plants with ease. It’s just killer on the electric bill! So I went back to LED.

If you are really ready to give up on LED, I’d strongly recommend t5 fluorescent or metal halide for veg and HPS for bloom. Or just use the LED’s for bloom. I find it much easier to flower under LED than veg.

Also, while I still haven’t 100% solved my issues with LED, I have definitely gotten better.

A big thing is DLI. You can download this free app called “PPFD meter” (the one by Home Studio inc.). It’s very accurate and has a built in DLI meter (daily light integral, the amount of PAR delivered over 24h).
You really need to stay in the DLI green zone with LED’s.

If you don’t have LED lights that can dim from 0-100% that would be my recommendation. Either add an aftermarket dimmer switch or get LED’s with dimmers.

You really need to watch the light levels with LED. The thing that has made the biggest difference for me is simply dimming the LED’s. My AC infinity LED I usually only run at 20-30% and even that can be too much believe it or not.

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Absolutely yes.

Heritage farms gave great advise. It’s similar to what I said in my long ass post. lol

As a long time grower that has been my experience as well. I have only been using LED for 3-5 years now, so I’m still learning with them. I started with using them for flower and still love them for flower. I easily get the same production off of 450-600 watts of LED as I did from 1000 watt HPS. But for veg I still struggle at times keeping plants healthy. I’ve only been using them for veg for maybe 3 years now. I’ve tried a # of different LED lights too. Some have been better than others. But all can cause similar issues to what you’re seeing, especially with my mother plants that stay under the LEDs for longer periods of time.

Check your local classified ads and Facebook marketplace for used t5 fluorescent lights. I got a bunch of the 4ft, 8 bulb t5 lights for $50 each (with the bulbs too).

The only problem with using fluorescent is that fluorescent light + bulb production is being discontinued. So if you buy them, I’d stock up on the bulbs now if you can. Bulbs last a pretty long time but you’ll eventually need replacements. You can get a case of 5 bulbs for a reasonable price if you look online.

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It really depends on how much you add and what the resulting color mix is , t5s and most all fluorescents have been banned production wise so we all have to adapt whether we like it or not as once the ones left are sold there gone.
There is a thread on here titled what I don’t like about leds or something close to that where I have posted a lot of my opinions/experience with the subject. I would suggest browsing it over and checking to see what the spectrum of those lights is.
Full spectrum is a labeling gimmick as far as I’m concerned and they are still heavy towards bloom spectrum most times. I can post pictures of the plants I have under the cheap leds I found to work best once home for any doubters
I have 50 watts of led covering what took 162 watts of fluorescence .
Next step ditch all t5s and drop from 486watts veg tent to 175 watt veg tent with more square feet covered :grin:

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What is rhe aci led you run at 30%.

Also ive done my last 3 year’s in 2011-2014 under Banks of 315, i loved them

Im going to add some t5 to my veg tents.

When you’re talking “not full spectrum” led, what’ is 5ge diodes used in the leds that garnished that opinion? As the spectral graph for the lm301h is pretty solid.

Talking blurple ones or modern Samsung 301’s?

No that’s not what I mean.
When they say full spectrum what do you think that means compared to other lights ?
How are other grow lights not full spectrum…
Unless it is a special type light most grow lights put out light from the blue to red end of the spectrum and what is considered a grow bulb is more heavy in the blue end replicating spring summer and bloom bulbs are heavy in the orange red side mimicking mid summer to fall.
These full spectrum led are almost all heavier in the bloom spectrum then veg and the color spectrum effects the plants in several ways.
I don’t mean that there not full spectrum but that label normally means balanced color ratios at best but often leaning towards bloom not veg and it upsets the plants.

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Do you have a picture that you can share that shows the spectrum analysis chart for your LED’s?

@Heritagefarms is the member I couldn’t remember the name of who has the solid information regarding these types of issues, and they even mentioned the thread I was thinking of:

@Heritagefarms you mention not enough green light and I often comment suggesting it’s too much/broad of green in the spectrum recipe for LED’s, whatever it is the ratios are off when problems are being observed and your comments are very valuable to help sort these things. HID isn’t perfect but seems to work well, LED’s when the spectrum recipe isn’t good does poorly, and LED’s with a good spectrum recipe or supplemented with whatever is missing seems to work very well.

For all the mentions of PPFD by different members I think it’s important but I think just as much or even more important is the quality of that light energy as it relates to the photoreceptors in a given plant. The spectrum soup.

Whenever there are problems like this here in the thread with LED’s my first thought is how it would be nice to see the spectrum analysis chart for the lights compared to for example a 400/600/1000 watt Hortilux HPS for relevance. Since the sun puts out more light energy outside the visible light spectrum, and since plants don’t have eyeballs like humans they probably don’t rely on the visible spectrum as much and more happens at the extremes of the visible light range and into the unseen like near far red, infrared, and uv. This could explain why HID lamps with their light energy mostly concentrated at the edges of the visible light spectrum have proven to do well compared to the LED arrays who don’t match similar well performing spectrum recipes. Whereas the LED’s that better match the ratios of HID lamps seem to do well enough for many to say they outperform the HID and are more efficient doing so.

I wonder if it’s possible to have plants tested for how many and which photo receptors they have, so that light recipes can be even more meticulously dialed in, does anyone know if that’s a possibility? Wondering if supplementing CO2 would help in some of these instances as well. Awesome topic it’s got my brain feeling a workout and it’s enjoyable. Many blessings and much love

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The old ones lacked green and uv is another subject but what I’ve found is the general balance of colors is off and once I ran leds with the correct blue to red ratios for veg all problems went away with out having to change anything else.
My veg room is in an area that gets down to 60f in the winter and up to 85 in the summer with little to no effects on the plants , vpd is not even taken into consideration , everybody is overthinking it trying to come up with any reason besides the lights, hard to accept for some and expensive learning curve , but I promise it’s the lights.

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ill also reiterate what a few have said or mentioned that may of been missed, LED growing one needs to consider running higher temps in comparison to hps/mh growing as the leaf surface temperature isnt the same, also air exchange in the tent can also be alot less because of alot less heat generated by leds.

Try going up to say 80-83f if you can, which you can lower your extraction rate to get temp and RH up if looking to do so.

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Yes this makes sense, thank you for sharing your experiences. Also @TeddyNuggets with the quality real world experience comments! Surely helping many members and many more who may just be lurking finding help.

I liken it to light being music and the light fixtures and lamps are the DJ and speakers. Some get the volume just right and play all the great music we can dance to, while others the beat is off and/or the volume is irritating. The light energy delivered to the plants is the music in which they dance to. Many blessings and much love

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The led lights that are working for me have a switchable spectrum and come from the hardware store , nobody wants to believe they work based on how generic they are but they do and that’s what matters to me :grin: Here is a pic when I tried them on veggie starts first , the last spectrum is what works best for veg , might try these out for a bloom run this winter.
25 watts each


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Oh yes, there are dotEdu studies and private studies on the effects of spectrum and intensity on cannabis growth and morphology. Many times these do build upon past knowledge such as Pr/Pfr phytochromes ratios, et al. Migro has created some accessible video on spectrum and growth. Such studies, along with economics, have generated what we see on the market today in terms of spectral balance.

As far as the photo-synthetic reception centers, the quantity varies by acclimatization of the plant to the light intensity. It goes both ways when moving into different environments. The most notable is low to high intensity while high to low tends to be more ‘hidden’ … but rest assured that plant will need to acclimatize by building new photo-synthetic reception centers under the newer and lower intensity lighting. Even more, light from the sun will have an intensity that is much more consistent top to bottom … so the plant is temporarily less efficient at the collection of photons particularly lower on the plant as it enters into a less intense environment.

Interesting thought. Don’t know but I’d surmise that the plant will temporarily not be able to capture enough photons and will be the limiting factor while the plants re-acclimatizes. The excess carbon in the Calvin cycle will have minimal effect as the generation of ATP is temporarily reduced due to the number of photosynthetic reaction centers available. My presumption is assuming that there is a step change in the light intensity.

Here is the spectrum and PPFD for sunlight 11AM Northeast long days:

Integral radiant (400-700nm): 341.7 W/m^2
Integral radiant (350-840nm): 483.8 W/m^2
PAR (400-700nm): 1580 umol / m^2 s
YPF (360-760nm) : 1412 umol / m^2 s
YPF/PFD: 0.89
PSS: 0.72
DLI index [12 hours] : 68.3

And, likewise, Fluence Spydr 2P PhysioSpec Indoor:

Integral radiant (400-700nm): 186.4 W/m^2
Integral radiant (350-840nm): 192.3 W/m^2
Lumens (m^2) : 54821
Spectrometer PFD (400-700nm): 889.56 umol / m^2 / s
Spectrometer PFD (350-840nm): 925.5 umol / m^2 / s
Quantum Sensor PFD (400-700nm): 850.4 umol / m^2 / s
YPF (360-760nm) : 791.86 umol / m^2 / s
YPF/PFD: 0.89
PSS: 0.86
DLI index [12 hours] : 38.4

As noted above, sunlight is comparatively intense at nearly ~1600 PPFD vs ~850 PPFD, in this instance. And, distance of the plant from the sun will not matter unlike fixtures.

There’s some example spectra here that may be of interest to those looking into spectra stuff (mostly LED though):

p.s. the YPF is a more modern take on the photosynthetic photon ‘yield’. It is weighted by spectra and extends further based on research on useable spectra. Here is an example YPF vs PAR. Each is integrated across the curves to create the PFD and YPF metrics:

Plants are capable of utilizing a broad range of spectra. Different spectra can affect plant morphology, as noted. Shade avoidance, efficiency, Pfr/Pr, etc.

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Just ordered 10 t5 fixtures and 2 25 packs of bulb’s, 25 in 6500k and 25 in 3000k

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